Nine years after Guy Turcotte killed his children, he is appealing his sentence.

The former cardiologist was found not criminally responsible at his first trial. He was sent to the Pinei Psychiatrist Institute and released in December 2012.

An appeals court overturned the verdict and Turcotte was required to stand trial again.

Following the second trial, Turcotte was found guilty in 2015 of the second-degree murders Anne-Sophie, 3, and Olivier, 5 and sentenced to life in prison without parole for 17 years.

He never denied killing his children.

Two years ago, Turcotte's lawyer Pierre Poupart filed an appeal of the sentence and the case is finally being heard in court.

"We're not talking about a psychopath, but a loving father", he said.

Poupart is not denying his client's guilt -- but he is arguing that 17 years without parole is too long to spend behind bars.

Poupart said that the sentencing judge should have taken Turcotte's mental status into effect when determining the sentence, and so given Turcotte the chance of being granted parole after ten years.

Poupart said the original judge, Andre Vincent, referred to the killings as ‘cold-blooded murders’ something Poupart said isn’t supported by the facts during the trial, adding that sentenced average between 10 and 15 years for second-degree murders.

Turcotte has undergone psychiatric treatment since his arrest and been determined to no longer pose a risk to society. Because he was deemed unlikely to reoffend, Poupart claims the court should shave a few years off Turcotte’s sentence.

Prosecutor Rene Verret told the three appellate judges that the 17-year delay before parole eligibility should be maintained, saying there were many aggravating factors, including the fact that Turcotte stabbed the children a total of 46 times, then tried to commit suicide.

"He knew what he was doing. A father who takes his children's lives commits one of the most serious crimes," said Verret.

“We all know the circumstances of the crime. There are no words to describe them these offences. We all know them, so of course we insisted a lot on those factors.”

The mother of the slain children and Turcotte's ex-wife, Isabelle Gaston, said the appeal makes it hard for her to cope with grief.

"I'm starting to look at it a different way, but yes it's very long and… it stole from me a lot of projects or maybe the chance for me to be a mother," said Gaston.

She said the lengthy case has taken its toll.

"I'm still fighting with the image in my head, with psychologists and psychiatrists, because that's the main battle for me is to try to get out of my head those terrible images," said Gaston.

“As a parent, you are parent one day and you're a parent all your life, so even if my children are not here physically, I will honour their memory and be there for them, be their voice,” she said.

Turcotte was not in court Tuesday and remains in prison while the appeal is being heard. The court is expected to rule in the coming months.